This invention relates to a biodegradable plastic composition. More particularly, this invention relates to a biodegradable plastic composition containing polyglycolide and one or more specific high molecular weight substances.
Plastics are widely utilized in daily life as various shaped articles such as films, bags and containers. As the majority of plastics is not decomposed in natural environment, however, a serious problem of environmental destroy or pollution due to waste plastics has now been raised with increase in the amount of plastics used. For example, a movement of prohibiting or limiting the use of plastics as packaging materials is being encouraged in recent years in Europe and America. Accordingly, the development of plastics decomposable (biodegradable) by microorganisms or enzymes in the soil is now being carried out widely.
In the past, polyglycolide was known to be one of the biodegradable high molecular compounds. This compound has a high melting point and so is excellent in heat-resistance, but has high crystallinity and is brittle. Accordingly, this compound alone has not yet been used practically as a plastic material.